Charge Transport Mechanism in p-Channel Tin Monoxide Thin-Film Transistors

Abstract

In this letter, we report on the charge transport mechanism in the p-type tin monoxide (SnO) thin-film transistors (TFTs) over a wide range of operation regimes and temperatures. From the temperature-dependent field-effect conductance measurements, the variable range hopping and the trap-limited band transport are considered as dominant charge transport mechanisms in the SnO TFT at temperatures below ~ 200 K (−73 °C) and above ~273 K (0 °C), respectively, in the subthreshold and transition regions. In the above-threshold region, the intrinsic field-effect mobility ( $\mu _{\mathsf {FEi}})$ decreases with an increase in temperature with a prefactor $\gamma \sim $ -0.36 in the $\mu _{\mathsf {FEi}}\sim {T}^{\gamma }$ law at temperatures ( ${T}\text{s}$ ) between RT and 353 K (80 °C). The observed temperature and gate overdrive voltage dependence of $\mu _{\mathsf {FEi}}$ suggests that the acoustic phonon scattering is the dominant physical mechanism limiting $\mu _{\mathsf {FEi}}$ in the p-type SnO TFT at realistic operating conditions [in the above-threshold region and at temperatures ranging from RT to 353 K (80 °C)].